Archimesh installing problems
seems like this has been solved on the thread

http://blenderartists.org/forum/showthread.php?315980-Archimesh-Architecture-elements-%28rooms-doors-columns-stairs-tile-roofs%29/page2

when you go to the github link https://github.com/Antonioya/blender/tree/master/archimesh



you need to click on the zip file then select raw and it will download correctly.